This invention relates to continuous transport apparatus whose transport speed is variable.
The invention is particularly, but not exclusively, applicable to a variable-speed moving walkway comprising a series of loads bearing members such as plates disposed along a continuous track including a transport path and a return path, with adjacent members overlapping, the load-bearing members being mounted on respective guided supports. The speed variation is obtained by varying the spacing of adjacent supports; each pair of adjacent supports is connected together by a respective flexible inextensible link, for example a chain or belt, which extends in a loop round angle-changing members such as pinion wheels or pulley wheels on the supports, the spacing of the angle-changing members on the same support being adjusted perpendicularly to the direction of transport so as to cause a corresponding inverse variation in the spacing of the adjacent supports parallel to the transport direction. The angle-changing members engage guide rails which extend along the track and whose spacing varies to vary the spacing of the angle-changing members on the same support and hence vary the support spacing and transport speed.
Such an apparatus may take the form of a variable speed walkway in which the transport speed is slow in the access and exit zones and is fast along the majority of the path in between. The apparatus may be driven by a motor acting on a few supports at a time in the high speed zone.